Perpetual Next - Carbonisation technology

Carbonisation technology

We believe in the power of carbonisation solutions

Perpetual Next firmly believes in carbonisation: a process to produce renewable carbon from bio-residues such as forestry residues, scrap wood, etc. Carbonisation is a process to produce renewable carbon from bio-residues such as forestry residues, scrap wood, etc. A technology that we have perfected in our unique carbon converter: C-Vertr. In our C-Vertr we use a process of thermochemical conversion of organic waste in an oxygen-deficient environment. 

Our carbonisation technology helps industries become fossil free and improve their carbon footprint of industrial processes. Without time-consuming, high captital investments in infrastructure. And carbonisation is scalable carbon removal solution.

Perpetual C-Vertr

Our Perpetual C-Vertr reactor is a Perpetual Carbon converter. It heats the feedstock with the syngas it generates in the process in a closed cycle. The material is conveyed through the length of the reactor and is progressively dried and then carbonised in an anaerobic atmosphere. Our C-Vertr reactor separates the combustion process from the carbonisation process. This separation has a positive effect on the mass yield (mass flow out/mass flow in), and thus on the financial performance of the process. Keeping these flows separate results in a controllable and homogeneous carbonisation process. This process is stable to run continuously and is inherently safe by design. 

Our C-Vertr reactor can be integrated in different kind of industries and plant layouts. With different footprints. We offer a smaller C-Vertr V4 installation of 12 x 8 x 5 meters (LxWxH) and a larger C-Vertr R2 installation of 35 x 15 x 12 meters (LxWxH). Additional space for control panels, MCC and construction access are also required and are site- and building-dependent. 

The design capacity is either 5.000-15.000 ton, or 20.000-30.000 ton in a range depending on feedstock and product grade. 

Many companies have experimented with heating organic residues in a low-oxygen environment, but only few have mastered carbonisation in such a way that it is consistent, efficient, of high quality and safe. 

C-Vertr in Dilsen-Stokkem and VÄGARI

Carbon conversion proces

A C-Vertr carbonisation line is part of three process steps of a plant solution:

1. Feedstock pre-processing

An organic residual stream: such as woodchips from branches or demolition wood, which are dried in an industrial dryer, most common are a drum dryer or a moving-belt dryer.

2. Primary C-Vertr carbonisation

Under a low-oxygen environment, the dried organic residues are heated. Volatile components from the organic residues are released, and progressively the material turns black and becomes biochar. Depending on the process time, the material is more or less carbonised, and contains a higher or lower percentage of carbon. The Perpetual Carbon then is cooled and fed to the next step.

3. Perpetual Carbon post processing

The Perpetual Carbon is ground, densified and can be pelletised to 6 mm cylindrical pellets or alternative densification form that can be easily transported and stored.

Perpetual Next - Flow chart

From feedstock to biocarbon

Feedstock is indirectly heated in the reactor with the flue gas coming from the combustion of the syngas. The syngas is self generated during the process in a closed cycle. The feedstock is conveyed along the length of the reactor and is progressively dried, then carbonised (a thermochemical treatment process) that is carried out under atmospheric pressure and in the absence of oxygen. Carbonisation upgrades a wide variety of raw organic residual streams into a homogeneous source of biocarbon. This final product is the remaining solid, dry, blackened material that is referred to as biocoal or biochar.

Graph: energy and carbon content as function of carbonisation temperatures. The measurements visible in the graph were taken in the range of 265 to 450 degrees. 

Perpetual Next - graph Energy and carbon content as function of torrefaction temperatures (265-450 degrees)

C-Vertr: input and output

Carbonisation technology is the most environmentally sustainable when it is used to process either tertiary biomass streams or waste streams. 

Tertiary feedstock streams are residuals that remain after use or consumption of a product, e.g., demolition wood and waste wood. 
Non-recyclable waste streams are a mix of non-recyclable waste, containing elements of plastics, textile, wood or paper which is the result of processing those waste streams to a level of smaller elements with a higher calorific value.

With the C-Vertr you can utilise this normally unsuitable input as clean heat supply for your installations. And as a fossil carbon replacement in general or as carbon sink. For many products like steel, cement, asphalt and insulation materials, biocoal can be used as source for process heating. 

Please have look at our biocoal and biochar section for further information.

Perpetual Next - Carbonisation technology advantages

Features and benefits of our C-Vertr R carbonisation technology

Under these conditions the tenacious fiber structure of the biomass feedstock is largely destroyed through the breakdown of hemicellulose and cellulose molecules. In addition, gases are emitted which are used to fuel the process resulting in a very energy efficient system.

Features Benefits  
Reactor that is indirectly heated and thermally self-sustaining Optimal, energy efficient heat transfer at maximum safety  
High continuous throughput Energy efficient and optimal integration possibilities for your plant  
Innovative carbonisation technology based on repurposed conveyor reactor technology Reliable technology with high availability and low maintenance  
Modular compact design Scalable to multiple carbonisation lines, controlling the process risks  
Reactor with 4 separate heating zones Optimal conversion and precisely controlling ratio of solids and gases, allowing reliable product output quality  
Integrated post-combustion chamber (oxidiser) to burn the process gas Self-sustaining process, requiring no external energy sources  
Exhaust cleaning system to secure safe emissions Ability to process low grade recycled wood  
Input of various grades and sizes of feedstock possible Minimal risk on feedstock shortages and cost increases  
Highly engaged support team with up to 20 years of carbonisation and over 12 years of operation experience in Dilsen-Stokkem (Belgium) and Vägari (Estonia) Available for you: the Perpetual Next experts in carbonisation and our network of partners, to decarbonise your business scale up and make impact for 'a beautiful new industry'  

Technical papers

This section contains a selection of our most relevant technical papers in the field of carbonisation for this segment application. These technical papers are mostly papers from our own Perpetual Next experts.

For all our technical papers, please visit our Knowledge page.

Perpetual Next - Shortlist of converted & analysed feedstocks

Perpetual Next shortlist of converted & analysed feedstocks


At Perpetual Next, we continue to analyse different types of feedstocks, options from different feedstock baskets, with different properties. All feedstocks have their advantages, it all depends on which bias you look at an opportunity. This document is the shortlist of feedstocks we have looked at so far in more detail.

Perpetual Next - Technical paper - Carbonisation of Solid Recovered Fuel (SRF) on industrial scale

Carbonisation of Solid Recovered Fuel (SRF) on industrial scale

Period 2011-2013

Solid recovered Fuel (SRF) is a fluff material obtained from non-hazardous domestic and industrial waste. This waste has been made smaller, dried and inerts, ferro and non ferro has been removed as good as possible. Also...

Perpetual Next - Technical paper - Pelletizing biocoal

Pelletizing biocoal

Producing optimal pellet quality with minimal energy consumption & wear on parts

To store and to transport carbonised material safe and at lower costs users request to densify this material by pelletizing. However it has become clear, that this densification process is rather critical and expensive...

Perpetual Next - Technical paper - Feedstock for carbonisation process

Biomass containing material as feedstock for the carbonisation process

An overview of different kind of feedstock in the carbonisation process

Different kind of biomass containing feedstocks have been tested by Perpetual Next Dilsen-Stokkem: mixed woodchips, acacia wood, eucalyptus wood, used untreated pine/spruce wood, treated used mixed wood, blends of...

Perpetual Next - Technical paper - Flue gas cleaning during the carbonisation process

Flue gas cleaning during the carbonisation process of low value biomass containing residual flows

Considerations for the method chosen and description of the flue gas cleaning installation

When using low value biomass containing residual flows as feedstock for the carbonisation process the increased chlorine and sulphur content of these flows will be partly present in the process...

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